Carbamoyl-2-pyrrolidinone compounds are disclosed as herbicides in French Patent No. 2018820, as horticultural fungicides in JP-A-52-25026, or as agents for improving the quality of citrus fruits in JP-A-54-66265, 55-81857 and 55-153763, whereas nothing has been described about their use in compositions for improving cerebral functions and in compositions for activating cerebral metabolism or protecting anoxic brain damage as disclosed in the present invention.
Furthermore, even if some of the compounds defined in the claims appended hereto should be included in the group of compounds represented by the broad general formulae in the above prior-art literature, they have been deleted during the examination procedures, or are not identified in any way in the detailed description of the specifications. Thus, they have not been disclosed in any way specifically and are novel compounds. The other compounds of the present invention are novel compounds which have not been described in any literature.
With an increase in the population of advanced ages in recent years, patients with senile dementia are expected to increase in number, posing a serious problem medically and socially. Although various antidementia drugs have been investigated and developed in view of the situation, no compounds have been provided with satisfactory efficacy up to date. It has been strongly desired to develop medicaments for treating the disease.
An object of the present invention is to provide novel carbamoyl-2-pyrrolidinone compounds which are very useful as medicaments for treating senile dementia, i.e., as cerebral function improving agents and cerebral metabolism activators or anoxic brain damage protectives.